Article packing apparatus



Filed April 15, 1953 ARTICLE PACKING APPARATUS 5 Sheets-Sheet 1 Fig.1.

INVENTORS Albert H. Merkner 8 Chester L Gutowski ATTORNEYS July 15, 1958A. H. MERKNER ET AL 2,842,912

- ARTICLE PACKING APPARATUS Filed April 15, 1953 5 Sheets-Sheet 2 Fig.2.

INVENTORS Albert H.Merkner& Chester L. Gmowski ATTORNEYS A. H. MERKNERETAL 2,842,912

ARTICLE PACKING APPARATUS July 15, 1953 Filed April 15. 1953 5Sheets-Sheet 3 INVENTORS Alberi H. Merkner 8 Chester L. Gutowski BY MMax:424

ATTORNEYS 5, 1958 A. H. MERKNER ETAL 2,842,912

' ARTICLE PACKING, APPARATUS Filed April 15, 1953 s Sheets-Sheet;

Fig.9.

INVENTORS Chester l. Gutowski I BY ATTORNEYS Albert H. Merkner 8; I

July 15, 1958 A, H. MERKNER ETAL 2,842,912

ARTICLE PACKING APPARATUS Filed April 15, 1955 5 Sheew-Sheet 5 INVENTORSAlbert H.Merkner 8 BY Chester L. Gufowski wmqswm ATTORNEYS United StatesPatent ARTICLE PACKING APPARATUS Albert H. Mcrlrner and Chester L.Gutowski, Pittsburgh, Pa., assignors to H. J. Heinz Company, Pittsburgh,Pa., a corporation of Pennsylvania Application April 15, 1953, SerialNo. 349,018

27 Claims. (Cl. 53--61) This invention relates to an apparatus forpacking plural layers of articles and more particularly for packingplural layers of cans in container boxes such as are customarilyprovided for shipment and storage.

While the article packing apparatus of this invention is primarily forthe purpose of packing cans in cardboard boxes or cartons, it is to beunderstood that its principles are applicable equally well to theproblem of packing other types of articles. Cans such as those commonlyemployed in the food industry are generally cylindrical in shape andmust be packed after filling in boxes for storage and shipment, twolayers of cans being usually packed in each case. The conventionalpacking apparatus for this purpose comprises an inclined track downwhich the cans are rolled on their sides to an assembling mechanismcomposed of tiers corresponding in number to the number of rows of cansto be packed where a single layer of cans is assembled. At theassembling mechanism, the operator places a box on its side with itsopen end facing the assembling mechanism and operates a pusher mechanismwhich moves the assembled layer of cans into the box. To insert a secondlayer of cans in the box, the pusher mechanism must be retracted inorder that another layer may be assembled in the tiers of the assemblingmechanism, and then the pusher mechanism must be operated a second timeto move the second layer into the box. The number of operations requiredof the operator and the inherent time delay between the variousoperations act to limit the production of this type of apparatus. Inaddition, this type of ap-. paratus results in frequent damage to thecans by reason of rolling on their sides, and the rolling movement ofthe cans to the assembly mechanism too often results in a stoppage ofthe can supply along the supply conveyor which further cuts downproduction.

To the endof reducing the time required for packing, this inventioncontemplates an apparatus in the form of a unit which will accept a boxor receptacle in which cans are to be packed, assemble the cans inlayers, Pack the layers of cans in the receptacle, and eject the caseproperly packed, all of these operations being performed in a mannerwhich is not dependent upon the constant attention of an operator.Generally stated, the apparatus of this invention comprises a novel form.of can collecting mechanism in which the cans are assembled insuperimposed layers and dropped into an underlying box or receptacle.The box to be filled is delivered to the collecting mechanism by anelevator on which it is placed by an operator or by a box conveyor, andafter filling of the box, the elevator returns it to a discharge stationwhere it is automatically ejected. In a'manner to be described, thevarious can assembling and charging operations incident to filling a boxwith two layers of cans are accomplished automatically in a cyclicmanner initiated by emplacement of the box on the elevator.

The specific structure of the apparatus, its operation and advantages,will become apparent from the following description.

ejected from the elevator.

2,842,912 Patented July 15, 1953 In the drawings, there is shown apreferred embodiment of the invention. In this showing:

Fig. l is a frontelevational view of an apparatus constructed inaccordance with the principles of this invention;

Fig. 2 is a side elevational view with the can delivery conveyingmechanism broken away;

Fig. 3 is a plan view of the apparatus shown in Figs. 1 and 2;

Fig. 4 is a fragmentary and detailed sectional view taken substantiallyalong the line IV-IV of Fig. 3;

Fig. 5 is a sectional view taken substantially along the line V-V ofFig. 3;

Fig. 6 is a sectional view taken substantially along the line Vl-VI ofFig. 3;

Fig. 7 is a plan view taken substantially along the line VIIVII of Fig.5;

Fig. 8 is a sectional view taken substantially along the line VlIlV-IIIof Fig. 7;

Fig. 9 is a plan view of the elevator which is employed for elevatingcartons to a can receiving position;

Fig. 10 is a sectional view taken substantially along the line XX ofFig. 9 showing the essential parts of the elevator mechanism in sideelevation; and

Fig. ll is a schematic view illustrating the essential parts of theapparatus diagrammatically and showing a control circuit in connectiontherewith.

in the drawings, the latter A designates an elevator mechanism whichreceives the cartons or boxes to be filled with cans for elevation to acan receiving or charging position immediately underneath a cancollecting and assembly mechanism B. In a manner to be described, themechanism vB collects the cans in two layers which respectively containseveral parallel rows, .7 and feeds such layers at the proper time intoa carton which is supported below on the elevator mechanism A.

Thereafter, the elevator mechanism A is lowered to its starting positionwhere the filled carton is automatically The cans are fed to theassembly mechanism B in parallel rows by a conveyor assembly C which,per se, forms no part of this invention. As will become apparent, thecycle of operations required for filling a carton with two or morelayers of cans begins with the emplacement of the can-receiving cartonon the elevatormechanis'm A, the subsequent operations all beingperformed automatically.

.As indicated above, the conveyor mechanism C forms .no part, per se, ofthis invention, and only a part thereof has been illustrated somewhatdiagrammatically in Figs. 2 and 3. It comprises a conveyor belt ionwhich cans 2 are supported in endwise position for delivery to the,assembly mechanism B. While the belt 1 has been indi-.cateddiagrammatically as a flexible belt, it will be formed in actualpractice of transversely extending slats connected together inconventional manner to provide the required flexibility. Guides in theform of laterally spaced vertical plates 3 which extend longitudinallyof the belt 1 provide parallel spaces through which the cans aredelivered in parallel rows, as best illustrated in Fig. 3, to theassembly mechanism B. The assembly mechanism .3 includes a transverselyshiftable frame 4 carrying vertically extending and laterally spacedplates 5 which, in the position illustrated in Fig. 3, provide parallelspaces in which the cans are received in parallel rows. A suitable formof mechanism C for conveying the cans to the assembly mechanism B isillustrated in Patent No. 2,219,817, issued October 29, 1940, to W. D.Kimball et al., which is referred to for a more detailed showing.

Can-assembling mechanism The can assembling mechanism B of thisinvention is mounted on vertical uprights 6 forming part of a supportingframework. The preferred embodiment of the mechanism B comprises threevertically spaced grids 7, 8 and 9 which are arranged in a manner bestshown in Fig. 5. The top grid 7 includes the transversely shiftableframe 4 and plates mentioned above. The frame 4 is supported on verticalsupports 10 by brackets 11 which provide a sliding support thereforenabling its position to be shifted transversely relative to thesupports 10. The plates are mounted on the frame 4 by brackets 12 anddepend from the frame 4 whereby the plates 5 may be shifted to the rightof the position shown in the various figures. In the position of theframe 4 shown in the rawings, the plates 5 are aligned with the conveyorguide plates 3 so that the cans may move from the conveyor C by asliding movement into the spaces between the plates 5.

Referring now to Figs. 7 and 8, it will be noted that the belt 1 istrained over a reel 14 and thus terminates short of the assemblymechanism B. To transfer the cans over the interval between the reel andassembly mechanism there is provided a thin sheet metal plate 15 whichis mounted on the supporting framework by brackets 16 at its transverseends. The plate 15 has one transversely extending edge 17 positionedadjacent the assembly B so that cans sliding over the upper surface ofthe plate 15 may be easily transferred to the assembly B. An oppositeedge 18 is positioned adjacent the end of the belt 1 at the point whereit starts to move downwardly over its reel 14 for accepting cans fromthe belt 1. The edge 18 is provided with a plurality of laterally spacedfingers 19 which respectively project underneath one of the spacesbetween adjacent conveyor guides 3. The fingers 19 are triangular inshape and have edges 20 which slope diagonally relative to the path ofcan movement so that the plate edge 18 has essentially a saw-toothconfiguration to facilitate sliding movement of the cans onto the uppersurface of the plate 15. As the cans move to the end of the belt 1, theytend to follow the movement of the belt downwardly over the reel 14 andthus tilt. The fingers 19 engage under the tilted lower ends of the cansso that the cans slide on to the upper surface of the plate 15. Byreason of the sloping edges 20 of the fingers 19, there is no abruptedge presented to the cans during their forward movement which mightotherwise act as. an

abutment and impede such forward movement.

The intermediate grid 8 comprises a hollow rectangular housing 21 whichis stationary and is mounted by brackets 22 on the supporting standards10. The housing 21 mounts a plurality of parallel plates 23 which have aspacing corresponding to the spacing of the spaced plates 5 of themovable grid 7. The plates 23 define spaces therebetween for thereception of cans. The sides 24 of the housing 21 provide the end plates23 and are extended below the level of the intermediate plates 23 asbest shown in Figs. 1 and 5. In the position illustrated in thedrawings, the upper edges 25 of the plates 23 are positioned centrallyof the spaced plates 5 of the movable grid 7 to form a support for thecans delivered to the movable grid 5 from the conveyor C. As the cansmove in parallel rows from the forward edge 17 of the supporting plate15, they slide over and are supported by the upper edges 25 of thestationary grid 8.

The extended lower portions of the sides 2 are slotted as at 26 toprovide a sliding support for the movable grid 9 which is a restraininggrid. The movable grid 9 comprises a rectangular frame 27 having pluraland spaced parallel restraining members 28. In the position illustratedin the drawings, the restraining members 28 are positioned intermediatethe plates 23 of the stationary grid 8 to provide a restraining supportengageable with cans in the stationary grid 8 for preventing downwardgravitational movement of the cans. The restraining grid 9 is shiftableto the right as viewed in the drawings to a position in which therestraining members 28 are aligned with the plates 23. Such shiftingmovement moves the V restraining members 28 out of engagement with thebot- .4. toms of the cans positioned in the stationary grid 8 andreleases the cans for downward gravitational movement through therestraining grid.

The lower edge of the housing 21 has plural spring leaves 29 dependingtherefrom for holding open the closure flaps of a carton which iselevated to receive a filling of cans from the assembly mechanism.

The structure of the can collecting and charging mechanism B will bebetter understood by referring briefly to the operation of the threesuperimposed grids 7, 8 and 9. When the spaces between the plates 5 ofthe mov-- able grid are filled with cans, the frame 4 is shifted to theright as viewed in the drawings to a position in which the plates 5 arealigned with the plates 23 of the stationary grid 8. This action movesthe cans out of supporting engagement with the top edges 25 of theplates 23, and the cans are thus released for gravitational movementinto the stationary grid 8. Downward gravitational movement of the cansthrough the movable grid is stopped by engagement of the bottoms of thecans with the restraining members 28. Movement of the frame 4 to theright in this manner moves the plates 5 of the movable grid 7 out oftheir aligned position with the conveyor guide plates 3 and to aposition in the path of movement of the cans from the conveyor C. Theplates 5 thus become effective to stop the forward movement of the cansby the conveyor C and the supporting belt 1 slides under the cans whiletheir forward movement is restrained in this manner. After the movablegrid 7 drops its charge of cans into the stationary grid 8, it isreturned to the position illustrated in the drawings to collect anotherlayer of cans. When the second layer of cans is collected by the movablegrid 7, the frame 4 is again shifted to the right to drop the secondlayer of cans into the stationary grid 8. Just before the second layerof cans are dropped into the stationary grid 8, the restraining grid 9,in a manner to be described, is shifted to the right to move therestraining members 28 out of supporting engagement with the cans in thestationary grid 8, as described above, to release the first layer ofcans for movement downwardly into a packing case on the elevatorunderneath the charging mechanism B. The restraining grid 9 ismaintained in its shifted position until after the second layer of cansare dropped into the stationary grid 8 so that the second layer of canswill gravitate through both the stationary grid 8 and the restraininggrid 9 without stoppage of downward movement by the restraining grid 9.

While the particular arrangement of superimposed grids 7, 8 and 9 asshown in the drawings and described above will charge a case with twolayers of cans, it will be understood that modifications permittingcharging a case with three or more layers are contemplated. For example,to charge a case with three layers of cans, it will only be necessary toincrease the depth of the stationary grid 8 so that it will accommodatetwo layers of cans therein. In such case, the restraining grid would beshifted once for every three shifting movements of the top grid 7instead of once for every two shifting movements as described above.While the top and bottom grids 7 and 9 have been described as beingshiftable and the intermediate grid 8 as stationary, it will be furtherunderstood that modified grid shifting arrangements may be employedwithout departing from the principles of this invention.

To shift the top grid 7 to the right as described above, a solenoid 30is provided. The solenoid 30 has an armature 31 which is connected at 32to one side of the frame 4. Upon energization of the solenoid, itsarmature 31 will be attracted to the right as viewed in Fig. 3 and carrywith it the frame 4. The other end of the frame 4 is connected with aspring 33 which is placed under tension by shifting movement of theframe 4 to the right and is effective to return the frame 4 to theposition illustrated in the drawings when the solenoid 30 isdeenergized.

In order to prevent energization of the solenoid 30 when any of thespaces between the plates may not be filled with cans, a pluralitycflimit switches 34 are provided. The limit switches 34 are mounted on asupporting bar 35 extended transversely of the apparatus, and haveoperating members 36 which project through open- .ings 37 in astationary plate 38 at the front of the grid 7. As best shown 'in Fig.'6, the forward movement of the cans between the plates 5 is limited byengagement of the foremost can in each row with the plate 38. As forwardmovement of therows of cans is stopped by the plate 38 in this manner,the operating member 36 will be engaged by the leading can in each rowto close the associated limit switch'34. In a manner to be described,the limit switches 34 are connected in series with a pair of energizingcircuits for the solenoid 30 so that the solenoid will not be energizedunless the top grid 7 has a full charge of cans therein.

The charging of a container with two layers of cans as described aboverequires a double operation of the solenoid 30. These two solenoidoperations are effected through a pair of limit switches 39 and 40 whichare positioned vertically above each other as best shown in Fig. 4-. Thelimit switches 39 and '40 are operated by a triangnlarly shaped cam 41mounted on a rotatable shaft 42 which also carries a ratchet wheel 43(see Fig. 5). The ratchet wheel 43 has six teeth which are arranged inthe path of an actuatingmember 44 carried by the shifting frame 4 of themovable grid 7. When the grid 7 is shifted to the right, the member 44engages one of the ratchet teeth on the wheel 43 and rotates the wheel43 and shaft 42 one-sixth of a revolution. The operating member 44 ispivoted so that return'm'ovement of the frame 4 will not change theposition of the ratchet wheel 43. A'pivoted pawl 45-is provided'toadditionally prevent rotation of the wheel 43 in a clockwise directionopposite to that in which it is moved by the member 44. Operation of theratchet wheel 43 in this manner rotates the triangular cam 41 throughone-sixth /5) of a revolution and moves one of its cam points out ofengagement with the operating member 46 for the limit switch 39 andanother of its-cam points into engagement with an operating member 47for the limit switch 40. In the next operation of the ratchet wheel 43and cam 41, a high point 'on the cam 41 is moved out of engagement withthe operating member 47 for the limit switch 40 and into engagement withthe operating member 46 for the limit switch 39. In this manner, thelimit switches 39 and 46 are opened and closed alternately at eachoperation of the movable grid 7, one of such limit switches being closedat all times. The manner in which the limit switches 39 and 4t?cooperate in a control circuit for the aparatus will be explained below.

Shifting movement of the restaining grid 9 to the right is efiected by asolenoid 48 having an armature 49 which is connected to the frame 27 ofthe movable grid 9. When the solenoid 4-8 is-energized, its armature 49is attracted to the right as viewed in the drawings and carries with itthe restraining grid 9. A spring 50 is connected to the other end of theframe 27 which is placed under tension when the grid 9 ismoved to theright and is effective to return the frame 9 to the position shown inthe drawings when the solenoid 48 is de-energized. In a manner to bedescribed, energization of the solenoid 48 is made dependent upon themovable grid 7 operating to collect two layers of cans. In other words,the solenoid 4-8 cannot be energized unless all of the limit switches 34have been actuated twice thereby insuring a double operation of thesolenoid 30 for each operation of the solenoid 48.

Elevator mechanism The elevator mechanism A, as indicated above, isprovided for elevating boxes or cartonsto a position underneath thecharging mechanism B for the reception of a charge of cans. The elevatormechanism in the various figures of the drawings is shown in its loweredposition. It includes a vertically movsble frame 51 carrying a pluralityof roller supports 52 which have their axes extending from front to rearof the frame 51. As has been further indicated above, the variousoperations incident to the filling of a carton with plural layers ofcans are made dependent upon the emplacement of a box in position on theroller supports 52. To properly position a box on the roller supports52, there is provided a centering mechanism which includes thehorizontal stop bar 55 supported at the back of the elevator bysupporting bars 54 at a point above the level of the rollers 52 andwhich provides a rear stop for limiting rearward movement of a box onthe rollers 52. As shown in Fig. 9, there is provided an arm 56connected to a plate 53 having a pivot connecdon 57 to one end of thestop 55 for engagement with one side of the box. A biasing spring 58 isprovided for biasing the arm 56 to the position shown in Fig. 9 in whichit will engage with one side of the box on the rollers 52. The otheredge of the frame 51 is provided with a stationary guide plate 59 whichis socured to the other end of the stop 55. Boxes or cartons'to befilled are placed on the elevator by a sliding movement endwise over theroller supports 52 until they engage with the rear stop '55. If the boxis not centered properly on the rollers 52, the arm 56 engaging with oneside of the box will move it laterally to a position in which its otherside engages with the guide plate 59.

Elevating movement of the platform 51 is controlled by a limit switch 60which is positioned at the right of the frame 51 as viewed in Fig. 9.The limit switch 6-) is mounted on a plate 61 carried by an arm62 (seeFig. 10) which extends forwardly from the stop bar "55 and carries theside guide plate 59. The limit switch 6%) is operated by'an arm 63having a pivotal connection at 64 to the switch mounting plate 61. Asshown in Fig. '9. the switch operating arm 63 has its outer end 65inclined and projecting forwardly through a space between the rear ofthe guide plate 59 and the rear stop 55 so that it will be pivoted in aclockwise direction to operate the switch 60 when a box is moved intoposition against the back stop 55 and the side stop 59. It willbe notedthat the end 65 of the switch operating lever 63 is positioned adjacentthe back stop 55 to prevent operation of the switch 60 unless the box isproperly positioned on the rollers 52. It is'not essential that the boxbe precisely centered since the spring leaves 29 projecting downwardlyfrom the charging mechanism B will center the box when it is raised toreceive a charge of cans. The switch operating arm 63 has a spring bias(not shown) for maintaining it in its unoperate'd position asillustrated in Fig. 9. In a manner to be described, operation of theswitch 60 by the arm 63 is necessary to initiate elevation of theelevator to thereby initiate the cycle of operations required to fillthe box.

Upward vertical movement of the elevator is guided by guide plates 67which mount spaced pairs of rollers-'63 having guiding engagement with avertically extending trackway 69 secured to the stationary standards 6.The guide plates 67 are secured to channels 66 which are in turnattached to the under side of the vertically movable frame 51.

A stationary supporting frame-work 76 is attached 'to the stationarystandard 6 and carries stop members "71 which engage with the under sideof the frame 51 to limit downward movement of the elevator. Upwardmovement is effected by an air or hydraulically operated cylinder '73mounted on the supporting frame-work'7tl. The cylinder 73 has a pistonrod 74 projecting therefrom for imparting upward movement to theelevator frame 51. The details of the cylinder 73 including itsoperating valves will be described in connection with'the operation ofthe apparatus upon reference to the schematicshowing of Fig. 11.

One of the channels 66 secured to the under side of the frame 51 carriesa switch operating element for operating control switches 76 and 77. Thecontrol switch 77 has an operating arm 78, as best shown in Fig. 2,positioned in the path of a roller 79 at the end of an arm 80 secured tothe member 75 so that upward movement of the roller 79 will actuate theswitch 77. As will be explained in connection with the showing of Fig.11, closure of the switch 77 is essential in order to effect the secondtransfer shifting operation of the top grid 7.

The switch operating member 75 also mounts an open ating member 81 whichwill engage and actuate an operating button 82 for the limit switch 76upon movement of the elevator to its uppermost position. As will beexplained in connection with the showing of Fig. l l, closure of theswitch 76 energizes a circuit for effecting lowering movement of theelevator.

The channel 66 mounts a second switch actuating mcm ber 83 forengagement with a roller 84 at the end of a switch operating arm 85 fora switch 86. Closure of the switch 86 is effected by upward movement ofthe actuating member 83 and is effective to energize a circuit to thesolenoid 48 for effecting shifting movement of the restraining grid 9.

Case ejecting mechanism To eject a filled case upon return of theelevator 51 to its lowered position, there is provided an ejecting bar88 which is secured to the outer ends of two piston rods 89 respectivelyhaving their inner ends connected to pistons 90 within air cylinders 91.The details of the cylinders 91 including the operating valve mechanismtherefor will be described in connection with the schematic view of Fig.11. At this point, it will be sufficient to indicate that admission ofair under pressure to the cylinder 91 will be effective to move theejecting bar 88 to the left as viewed in Fig. 1. Movement of theejecting bar 88 to the left in this manner causes it to strike thefilled case supported on the rollers 52 and the momentum imparted to thecase will cause it to roll over the rollers 52 and off of the elevator.Suitable conveyor mechanism (not shown) may be provided at the end ofthe frame 51 for receiving and carrying away the ejected case.

In connection with the ejection of a filled case from the elevator,attention is directed to the fact that the pivotal mounting of the casepositioning bar 56 as shown in Fig. 9 provides for the ejectingmovement. As the case is ejected, the bar 56 is pivoted in acounter-clockwise direction through an angle of 90 so that it will notinterfere with movement of the filled case from the elevator mechanism.As soon as the case has moved off the elevator, the biasing spring 58will return the centering bar 56 to the position shown in Fig. 9 whereit will be effective again to center the next box placed on the elevatorfor a filling operation.

The ejecting operation of the bar 83 is initiated by a limit switch 92mounted on the supporting frame 70 as shown in Fig. 2. The limit switch92 has an operating button 93 which is actuated by a pawl 94 which ispivoted at 95 to a bracket 96 secured to one of the channels 66. Thepawl 94 can pivot between stops 97 and 98 and has a gravity bias forengagement with the stop 98. Upon upward movement of the elevator, thepawl 94 is pivoted upon engagement with the switch operating button 93without actuating the switch 92. When the elevator is returned to itslower position, the stop 98 prevents pivotal movement of the pawl 94 andthe button 93 is actuated to close the switch 92. The stop 97 isprovided only for limiting the free pivotal movement of the pawl 94during upward movement of the elevator.

Operation structural elements of the apparatus have been shown Cirdiagrammatically and are designed by the same numerals applied to Figs.1 through 10. The control circuits are designated by letters to bereferred to and are energized when any circuit portion is completed froma positive to a negative terminal, the positive and negative terminalsbeing indicated diagrammatically by plus and minus signs.

The various parts illustrated in Fig. 11 are shown in the relativepositions which they occupy prior to starting operation of the apparatusand before any cans have been delivercd to the upper grid 7. Theapparatus is placed in operation by starting up the conveyor C todeliver cans to the upper grid 7. When each of the spaces in the uppergrid 7 is filled with cans, the limit switches 34 all close to completea circuit a for energizing the solenoid 30 through a branch circuit band the limit switch 40, the limit switch 40 being closed when theapparatus is started and the limit switch 39 being open. Energization ofthe solenoid 30 shifts the grid 7 to the right to drop the first layerof cans into the stationary grid 8 into a position supported on therestraining grid 9. Shifting movement of the frame 4 to the rightactuates the ratchet wheel 43 through the operating dog 44 to rotate theshaft 42 and cam 41 one-sixth (Vs) of a revolution to open the limitswitch 40 and close the limit switch 39. Opening the limit switch 40deenergizes the solenoid 30 so that the spring 33 becomes effective toreturn the upper grid 7 to a position in which it is effective tocollect another layer of cans.

Collection of the second layer of cans effects a second closure of thelimit switches 34 thereby setting up a second circuit for energizing thesolenoid 30 for shifting the upper grid 7 to the right a second time.This second circuit includes the branch circuit 0, the limit switch 39and the circuit elements d and e, the circuit element e being connectedto the solenoid 30 through one terminal of the limit switch 40. At thistime, the solenoid 30 is not energized due to the limit switch 77between the circuit elements 11 and e being open. The solenoid 30 willnot act a second time until after a box is placed on the elevator 51.

Emplacement of a box 99 on the elevator 51 initiates raising movement ofthe elevator. This is accomplished by the box closing the limit switch60 through cooperation of the box centering elements 56 and 59 and theactuation of the limit switch operating lever 63 as described above inconnection with Fig. 9. Closure of the limit switch 60 energizes asolenoid 100 through the circuit elements I and g, the limit switch 39which was closed by the first shifting operation of the grid 7, branchcircuit 0, and circuit a which it will be recalled was closed by thesecond closure of the limit switches 34 when the upper grid 7 collecteda second layer of cans. Energization of the solenoid 100 is essentialfor imparting :1 raising movement to the elevator and attention isdirected at this point to the fact that closure of the limit switch 60by emplacement of a box on the elevator will not cause the elevator tostart up unless the second layer of cans has been collected in the uppergrid 7.

Energization of the solenoid 100 moves a valve element 101 to the leftas viewed in Fig. 11 to connect an air supply conduit 102 through avalve casing 103 to a conduit 104 for delivering air under pressure tothe lower end of the elevator cylinder 73. The pressure so admitted tothe cylinder 73 acts on the piston 105 to move the piston rod 74 andelevator 51 connected thereto upwardly.

As the elevator moves upwardly, limit switches 86 and 77 are closed, thelimit switch 86 being closed by the operating element 83 and the limitswitch 77 being closed by the roller 79 actuating its operating arm 78.Closure of the limit switch 86 closes a circuit h for energizing thesolenoid 48 to shift the restraining grid 9 to the right so that twolayers of cans may drop therethrough into the box on the elevator.Closure of the limit switch 77 connects the circuit elements d and e toprovide a second energizing circuit for the solenoid 30. This secondenergization of the solenoid 3i? shifts the top grid 7 to the right todrop the second layer of cans into the stationary grid 8. In thepreferred practice of the invention, closure of the limit switches '36and 77 are timed in such manner that the limit switch 86 closes aninstant ahead of closure of'the limit switch 77'. In this manner,downward movement of the first layer of 'cans into the .box is startedjustprior to movement of the second layer of cans into the grid 8, andthe second layer of cans gravitates through the grids 8 and 9 into'thecase without having their downward movement stopped either by the firstlayer of cans or by the restraining grid 9.

When the grid 7 is shifted to the right by energization of the solenoid30 through closure of the switch 77, the ratchet wheel 43 is actuated torotate the cam 41 another partial revolution to open the switch 39 andclose the switch 40. Opening of the switch '39 deenergizes solenoid100and deenergizes the solenoid 30 so that the grid 7 is returned to theleft to pick up another layer of cans. .To-prevent tooirapid a returnmovement of the grid '7, a'retarding device 106, which may be anysuitable form ofmechanical dash-pot connected directly with the solenoidarmature, or a time delay relay in the energizing circuit for thesolenoid 30, is provided. It is necessary to delay the return movementof the grid 7 at this time since its immediate return would otherwiseresult in a third energization of the solenoid 30 through closure of thelimit switches 34 in the circuit a and the branch circuit b through thelimit switch 40. Premature operation of the grid 7 in this mannerwouldresult in a third layer being dropped into the stationary grid 8prior to return movement of the grid 9 to its restraining position. Thedelayin return movement of the grid 7 by the retarding device 106 isadjusted to insure return movement of the grid 9 before another layer ofcans can be collected by the upper grid 7. After the retarding grid 9returns to the position shown in Fig. 11, the top grid 7 may operate todrop a layer of cans into the stationary grid 3 where it will remainuntil another box is placed on the elevator.

The solenoid 48 is also provided with a retarding device 107, similar tothe retarding device 166for the solenoid-3t}, toprevent return of therestraininggrid 9 to its restraining position before the second layer ofcans has gravitated therethrough.

When the elevator moves to its uppermost limit of travel, the limitswitch .76'is closed by the operating member S1 carriedby the elevator.Closure of the switch 76 c'omplete's'a circuit i forenergizinga-solenoid 108. The solenoid 108 returns'the valve 101 to the positionshown in Fig. .11 thereby interrupting the connection of the air .supply.line 102 to the elevating cylinder 73. At the same time, the conduit104 connects the lower end of "thercylinder 103 :to the atmospherethrough a port 109 in 'the .valve casing'103. The elevator will thenreturn to its lower position by :gravity, and a manually adjustablevalve 110 .is provided for controlling the admission of air to'the upperend of the cylinder to thereby control its As the elevator'moves to itslower position, the ejecting bar 88'is operated to eject the box 99 asdescribed above. This is accomplishedby the'pa'wl'94closing the limitswitch 92 to complete an energizing circuit m for a solenoid 111.Energization of solenoid 111 moves valve element 112 in casing 113 tothe right 'tocotmect the conduit 114 with an air supply conduit 115. Atthe same time, conduit 116 is connected to the atmos'phere 'through'a'port 117 in the casing 113.

"Connection-ofthe conduit. 1 14 with the air supply conduit 1 in thismanner supplies air under pressure to the cylinder91formoving'the piston90 and ejector bar 88 110 :therleft as viewed inFig. 11 to eject afilled case from the elevator.

Movementiof the piston90 to the left carries with it a, switch operatingmember 118 which closes a switch 119 'at the endof the ejecting movementof;tl1e1piston 90.

Closure of the switch 119 energizes a circuit n for a cally and may beany conventional type suitable to the operations described. Asillustrated they are of the piston type and remain in the :position towhich they are moved by momentary energization of one of'the solenoidsuntil such time as the-other of the .solenoids is operated, it not beingnecessary to'maintain energization of a solenoid to have the valveremain in:any selected-position.

From the foregoing, it will be apparent that the apparatus of thisinvention is eiiective to pack a box with plural layers of cans,it'being only necessary to place an empty box on the elevator.Emplacement of the box on the elevator may be either a manual orautomatic operation as the circumstances may require and is efiective toinitiate the various operations incidental to charging the box with aplural layer of cans. Emplacement of the box on the elevator iseffective to initiate elevation of the elevator, and particularattention is directed to the fact that upward movement of the elevatorwill take place only if the-can assembling mechanism B is in'conditionto charge the box with the required number of layers of cans. in otherwords, emplacement of the box on the elevator will not be effective toinitiate its upward movement until the top layer of cans has beencharged into the top grid 7. As upward movement of the elevat'or takesplace, the controls for the charging operation of the assembly mechanismB are operated in timed sequence to fill the box with the proper numberof layers of cans. Attention is also directed to the fact that thesequential operation of the charging assembly mechanism B is responsiveto emplacement of a box on the elevator and to upward movement of theelevator. As this upward movement of the elevator takes place, closureof switch 77 results in the final shifting movement of the top grid 7and in an operation of the cam 41 to transfer control from the switch 39to the switch 40. Closure of switch 40 in effect takes control of theoperation of the assembly mechanism B away frorn'the elevator, but itwill be noted that the next shifting movement of the top grid 7, throughoperation of cam 41 and the closure of switch 39 and opening of switch40, returns control of the assembly mechanism B to the elevatormechanism. The operation of'the apparatus is thus continuous and isdependent only upon the conveyor C operating "to deliver cans and uponemplacement of empty boxes on the elevator.

While the above specification and accompanying drawings illustrate anddescribe one specific embodiment of the invention, it will be understoodthat this is merely by way of illustration, and that various changes andmodi 'fication's may be made therein'within the contemplation of theinvention and underthe scope of the following claims.

We claim:

1. 'In anarticle packing machine, the combination with a supply tablefor moving articles to be packed forwardly in pluralparallel rows, of apacking mechanism comprising a transversely movable grid having spacedparallel tational movement of articles through said stationary grid butmovable transversely into positions in alignment with said plates toallow articles to gravitate through both said stationary grid andrestraining grid.

2. An article packing mechanism comprising a transversely movable gridhaving spaced parallel members providing spaces therebetween in whichthe articles to be packed are received in rows, a stationary gridunderneath said movable grid formed of spaced parallel plates the upperedges of which provide a temporary support for the articles received insaid spaces, and a transversely movable restraining grid formed ofspaced parallel members normally occupying positions intermediate andparallel to said plates for restraining gravitational movement ofarticles through said stationary grid but movable transversely intopositions in alignment with said plates to allow articles to gravitatethrough both said stationary grid and restraining grid.

3. An article packing mechanism comprising at least three superimposedgrids respectively formed of spaced parallel members providing spacestherebetween for receiving the articles to be packed in rows, one ofsaid grids being stationary and the other two being movable transverselyrelative thereto, and means for actuating said movable grids in asequential manner to provide for the gravitation of plural layers ofarticles through the bottom one of said grids.

4. An article packing mechanism comprising at least three superimposedgrids respectively formed of spaced parallel members providing spacestherebetween for receiving the articles to be packed in rows, themembers of the intermediate and bottom grids respectively occupyingpositions intermediate the members of the overlying grid whereby theyare effective to restrain gravitational movement of the articles out ofthe spaces between the members of the overlying grid, at least one ofsaid grids being transversely movable relative with respect to one ofthe other of said grids whereby the members of two grids are movedrelatively into positions of alignment with each other to allowgravitational movement of articles from the spaces between the membersof an overlying grid into the spaces between the members of anunderlying grid.

5. An article packing mechanism comprising at least three superimposedgrids respectively formed of spaced parallel members providing spacestherebetween for receiving the articles'to be packed in rows, themembers of the intermediate and bottom grids respectively occupyingpositions intermediate the members of the overlying grid whereby theyare efifective to restrain gravitational movement of the articles out ofthe spaces between the members of the overlying grid, two of said gridsbeing transversely movable relative with respect to the other of saidgrids whereby the members of two grids are selectively moved relativelyinto positions of alignment with each other to allow gravitationalmovement of articles from the spaces between the members of an overlyinggrid into the spaces between the members of an underlying grid, andmeans for operating said transversely movable grids in a sequentialmanner to efiect gravitation of said articles in plural layers throughthe bottom one of said grids.

6. In a machine for packing articles in superimposed layers, means forsequentially collecting layers of articles to be packed, means forreceiving each said layer from said collecting means, and meanssequentially operable to release said layer and a second collected layerfor simultaneous gravitational movement into a packing case positionedunderneath said receiving means.

7. In a machine for packing articles in superimposed layers, receivingmeans in which a layer of articles to be packed may be deposited andincluding means for restraining the articles against gravitationalmovement therefrom, means automatically operable for collecting the I,

7 articles in layers and depositing said layers in said receiving means,and means for operating said restraining means to release a plurality oflayers of articles in said receiving means for gravitational movementinto a packing case.

8. in a machine for packing articles in superimposed layers, receivingmeans in which a layer of articles to be packed may be deposited andincluding means for restraining the articles against gravitationalmovement therefrom, means for collecting and delivering the articles inlayers by gravity to said receiving means, and means for sequentiallyoperating said restraining means to release the plurality of layers ofarticles from said receiving means for gravitational movement into apacking case.

9. In a machine for packing articles in superimposed layers, receivingmeans in which a layer of articles to be packed may be deposited andincluding means for restraining the articles against gravitationalmovement therefrom, means operable in sequence for collecting anddelivering a first layer and then a second layer of articles to saidreceiving means, means for operating said restraining means to releasesaid first layer for gravitational movement into a packing case wherebythe second layer deposited by said collecting means may gravitate intosaid case without being subjected to the restraining action of saidreceiving means.

10. In an article packing machine, the combination with a supply tablefor moving articles to be packed forwardly in plural parallel rows, of apacking mechanism comprising a transversely movable grid having spacedparallel members providing spaces therebetween in which the articles arereceived in rows from said table, a stationary grid underneath saidmovable grid formed of spaced parallel plates the upper edges of whichprovide a temporary support for the articles received in said spaces,means operated in response to filling of the spaces between said memberswith articles for shifting said movable grid to a position with saidmembers in alignment with said plates to drop a first layer of articlesinto said stationary grid, a restraining grid positioned underneath saidstationary grid and having spaced parallel restraining members normallyoccupying positions intermediate and parallel to said plates forengagement with the articles of said first layer to restraingravitational movement of such articles through said stationary grid,and means responsive to a second operation of said shifting means formoving said restraining grid to a position with its restraining membersaligned with said plates whereby said first layer of articles and asecond layer of articles fed to said stationary grid by the secondoperation of said shifting means may gravitate through said restraininggrid. 11. In an article packing machine, the combination 'with a supplytable for moving articles to be packed forwardly in plural parallelrows, of a packing mechanism comprising a transversely movable gridhaving spaced parallel members providing spaces therebetween in whichthe articles are received in rows from said table, a stationary gridunderneath said movable grid formed of spaced parallel plates the upperedges of which provide a temporary support for the articles received insaid spaces, each of said spaces having a limit switch at one endthereof which is closed in response to such space being filled with arow of articles, a circuit in which said switches are connected inseries, and an actuating device controlled by said circuit for shiftingsaid movable grid to a position with said members in alignment with saidplates to drop a first layer of articles into said stationary grid.

12. In an article packing machine, the combination with a supply tablefor moving articles to be packed forwardly in plural parallel rows, of apacking mechanism comprising a transversely movable grid having spacedparallel members providing spaces therebetween in which the articles arereceived in rows from said table, a stationary grid underneath saidmovable grid formed of a temporary support for the articles received insaid spaces, each of said spaces having a limit switch at one endthereof which is closed in responseto such space being filled with a rowof articles, a circuit in which said switches are connected in series,an actuating device controlled by said circuit for shifting said movablegrid to aposition with said members in alignment with said plates todrop a first layer of articles intosaid stationary grid, a restraininggrid positioned underneath said stationary grid and having spacedparallel restraining members normally occupying positions intermediateand parallel to said plates for engagement with the articles of saidfirst layer to restrain gravitational movement of such articles throughsaid stationary grid, and actuating means for moving said restraininggrid to a position with its restraining members aligned with saidplates.

13. A machine as claimed in claim 12 characterized by the provision ofmeans responsive to a second closure of said limit switches forrendering said actuating means operable.

14. A machine as claimed in claim 12 characterized by the provision of acontrol switch for operating said actuating means, and means operativein response to a second closure of said limit switches for closingsaidcontrol switch.

15. A machine as claimed in claim 14 characterized by said last-namedmeans including an elevator for raising a receptacle in which thearticles are to be packed to a position underneath said restraininggrid, and an operating member carried'by said elevatorfor closing saidcontrol switch. 7

16. Amachine as claimed-in claim 12 characterized by the provisionofa-control switch for operating-said actu'ating means an-elevator forraising a receptacle in which the articles are to be packed to a packingposition under said restraining grid, means responsive to a secondclosure of said limit switches for operating said elevator, andanoperatingmember carried by said-e'le'vatorfor closing said controlswitch.

17. An article packing mechanism comprising at least three superimposedgrids respectively formed of spaced parallel members providing spacestherebetween for receiving the articles to be packed in rows, themembers of the intermediate and bottom grids respectively occupyingpositions intermediate the members of the overlying grid whereby theyare effective to restrain gravitational movement of the articles out ofthe spaces between the members of the overlying grid, means for shiftingthe top and intermediate guides relative to each other to a positionwith their parallel members in vertical alignment with each other todrop the articles in the top grid into the intermediate grid, and meansfor shifting the intermediate and bottom grids relative to each other toa position with their parallel members in vertical alignment with eachother to release the articles in the intermediate grid for gravitationthrough the bottom grid.

18. A packing mechanism as claimed in claim 17 characterized by theprovision of a control means for efiecting a single operation of theshifting means for the intermediate and bottom grids in response to adouble operation of the shifting means for the top and intermediategrids whereby two layers of articles will gravitate through the bottomgrid in response to said single operation of the shifting means for saidintermediate and bottom grids.

19. A packing mechanism as claimed in claim 17 characterized by theprovision of a control means in including a first means for effecting adouble operation of the shifting means for said top and intermediategrids, and a second means operated in response'to said first meanseffecting said double operation for effecting a single operation of theshifting means for said intermediate and bottom grids.

20. A packing mechanism as claimed' in claim 19 characterized by saidfirst means comprisinga main control circuit having two branch circuitsrespectively having control switches therein, means alternativelyoperable'in response to operation of the shifting means for the top andintermediate grids for opening one of said switches and closing theother of-said switches whereby only .one of said branch circuits isclosed through its control switch at any given instant, and by saidsecond means comprising a circuit including an operating switch andmeans responsive to closure of the control switch closed by the secondoperation of said alternatively operable means foractuati'ng saidoperating switch.

21. A packing mechanism as claimed in claim 19 characterized by saidfirst means comprising a main control circuit having two branch circuits"respectively having control switches therein, means alternativelyoperable in response to operation of the-shifting means for the topandintermediate grids for opening one of'said switches and closing theother of said-switches'whereby only one of said branch circuits isclosed through its control switch at any given instant, said maincontrol circuit having a plurality of limit switches-therein, each ofsaid limit switches being respectively positioned at the end of one ofthe spaces of the top grid and being closable by articles filling thespace in which it is positioned, said shifting means for thetop andintermediate'grids being operable only upon closure of all of said limitswitches and one of said control switches, and by said second meanscomprising a circuit including an operating switch and meansresponsiveto closure of the'control switch closed by the secondoperation of said alternatively operable means for actuating saidoperating switch.

22. An article packing mechanism comprising at least three superimposedgrids respectively formed of spaced parallel members :providing spacestherebetween for receiving'the articles to be packed in rows, themembers of the intermediate and bottom grids respectively occupy ingpositions intermediate the'members of'the'overlying grid whereby theyare effective to restrain gravitational movement of the articles out ofthe spaces between the members of the overlying grid, a first actuatormeans for effecting relative shifting movement between said top andintermediate grids to a position in which articles in the top grid maygravitate into the intermediate grid, means controlling the operation ofsaid first actuator means comprising a main control circuit havingplural limit switches connected in series therein, each of said limitswitches being respectively positioned at the end of one of the spacesin the top grid and being closable by articles filling the space inwhich it is positioned, and first and second branch circuits connectedwith said main control circuit and respectively having control switchestherein, the control switch in said first branch circuit being closedwhereby closure of said limit switches completes a circuit through saidfirst branch circuit to effect a first operation of said actuator means,means alternately operable in response to each operation of saidactuator means for opening the control switch in one of said branchcircuits and closing of the control switch in the other of said branchcircuits, closure of the control switch in said second branch circuit bysaid alternately operative means being efiective to set up a secondcircuit including said main control circuit and second branch circuitfor efiiecting a second operation of said actuator means, a secondactuator means for effecting relative shifting movement between saidintermediate and bottom grids to a position in which articles in saidintermediate grid may gravitate through the bottom grid, and meansresponsive to closure of the control switch in said second branchcircuit for efiecting operation of said second actuator means.

23. An article packing mechanism comprising at least three superimposedgrids respectively formed of spaced parallel members providing spacestherebetween for receiving the articles to be packed in rows, themembers of the intermediate and bottom grids respectively occupyingpositions intermediate the members of the overlying grid whereby theyare elfective to restrain gravitational movement of the articles out ofthe spaces between the members of the overlying grid, an elevator forraising a receptacle in which the articles are to be packed in layers toa filling position underneath said grids, a first actuator means forefiecting relative shifting movement between said top and intermediategrids to a position in which articles in the top grid may gravitate intothe intermediate grid, means controlling the operation of said firstactuator means comprising a main control circuit having plural limitswitches connected in series therein, each of said limit switches beingrespectively positioned at the end of one of the spaces in the top gridand being closable by articles filling the space in which it ispositioned, and first and second branch circuits connected with saidmain control circuit and respectively having control switches therein,the control switch in said first branch circuit being closed wherebyclosure of said limit switches completes a circuit through said firstbranch circuit to effect a first operation of said actuator means, meansalternately operable in response to each operation of said actuatormeans for opening the control switch in one of said branch circuits andclosing of the control switch in the other of said branch circuits,circuit means responsive to closure of the control switch in said secondbranch circuit for effecting elevation of said elevator, closure of thecontrol switch in said second branch circuit being effective to set up asecond circuit for efiecting a second operation of said actuator means,a switch closed in response to raising movement of said elevator forrendering said second circuit operative, a second actuator means foreffecting relative shifting movement between said intermediate andbottom grids to a position in which articles in said intermediate gridmay gravitate through the bottom grid into the receptacle on theelevator, and a control switch closed in response to elevating movementof said elevator for operating said second actuator means.

24. A mechanism as claimed in claim 23 characterized by the provision ofa switch which is closed by the emplacement Of an empty receptacle onsaid elevator for rendering operative the circuit means for effectingelevation of the elevator.

25. A mechanism as claimed in claim 23 characterized by the provision ofa limit switch which is closed in response to movement of the elevatorto an elevated position in which the articles gravitating through saidbottom grid are deposited in the receptacle carried thereby, and meansresponsive to closure of said limit switch for lowering the elevator tocondition the mechanism for repeating its cycle of operations.

26. A mechanism as claimed in claim 23 characterized by the provision ofa receptacle ejecting apparatus for ejecting a filled receptacle fromsaid elevator, and means responsive to movement of the elevator to itslowered position for operating said ejecting apparatus.

27. A mechanism as claimed in claim 26 characterized by said ejectingmechanism comprising a cylinder having a piston therein, reversiblevalve means controlling the admission of fluid pressure to said cylinderfor effecting ejecting and return movements thereof, said last namedresponsive means including a switch operated by the elevator foractuating said valve means to effect an ejecting movement of the piston,and a switch closed in response to movement of said piston for reversingsaid valve means for effecting a return movement of said piston.

